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I’m letting you in on my family’s favorite easy brownie recipe, with all my best brownie mix hacks to make box brownies so much better! Just a few additional “secret ingredients” and no one will ever know your brownies came from a box!

Normally I don’t comment on these kinds of recipes, but it was so good. Without a doubt the best brownies I’ve ever had- including the countless ones I’ve made from scratch and even the deluxe brownie at my favorite restaurant- these simple modifications to a box of brownie mix make it the best brownies ever. Period. 

-Grace
hand holding a slice of a brownie
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Box mixes are so convenient. Bless the person who developed that amazing idea.

There should be no shame in using a brownie box mix.. but sometimes you want the box of brownie mix to taste more homemade. That’s where box brownie mix hacks come into play!

3 brownies in a stack on gray plate with blue linen underneath

Tried and Tested Brownies Box Recipe

We tested a lot of brownie mix hacks so we could come up with our best easy brownie mix box recipe. I tried and retried this recipe about 9 times in total!

brownies cut into squares in baking pan

Boxed Brownie Hacks: Doctored up Brownies Box

A traditional box brownie mixes call for water, eggs and vegetable oil. It’s all about adding ingredients to the brownie mix to give the brownies better texture & taste.

We want boxed brownie mix to taste like homemade brownies, like fudgy brownies, where the top of the brownies have that shiny appearance with an ultra fudgy texture.

How to make Box Brownies Better: Extra Ingredients You’ll Need

  • Add melted butter – makes the chocolate flavor richer compared to vegetable oil
  • Use buttermilk or whole milk – makes the brownie richer and taste more homemade
  • Add cocoa powder – adding additional cocoa powder makes the brownies more chocolate-y
  • Add in chocolate chips – this will give the brownies texture and enhance their chocolate flavors
  • Add espresso powder – makes the chocolate flavor richer, and the brownies will NOT taste like coffee. Instead of espresso powder, use 1/4 cup brewed strong coffee or 1 & 1/2 teaspoons instant coffee.

We actually tried this recipe with and without espresso powder and in a blind taste test, everyone preferred the brownie recipe with espresso powder because it tasted more chocolate-y.

Where to buy espresso powder

You can purchase espresso powder in the baking aisle of your grocery store or on amazon. 

brownie being removed from pan on metal spatula

Lazy Girl Brownie Mix Hacks

Here’s the BEST part for making box brownies better – you combine all of those ingredients and the brownie mix in a bowl, and beat it together with an electric mixer.

No adding each ingredient one at a time – add them all at ONCE! Let’s rejoice, these are the ultimate easy brownies for a crowd.

How to Make Boxed Brownies Better

  1. Preheat the oven to 350ºF. 
  2. Line a 8×8 inch square pan with parchment paper and spray with non-stick cooking spray. Set aside.
  3. Combine and mix. In a mixing bowl, combine the eggs, melted butter, buttermilk, brownie mix, cocoa powder and espresso powder and beat with an electric mixer on low until combined, about 1 minute. 
  4. Pour the brownie batter into the prepared pan. Spread evenly with a spatula.
  5. Bake for 37-40 minutes or until a toothpick inserted in the center comes out clean.
  6. Allow the brownies to cool. Remove the brownies from the pan using the parchment paper. Slice and serve. 
brownies laying on their side sliced into squares arranged in a grid pattern

Boxed Brownie Hacks: Testing with Eggs

Generally the more eggs you add to a brownie recipe, the cakier the brownie will be. That’s why it’s a good idea to stick with 2 eggs, which is typically the amount that the back of the box calls for.

However, you can add an additional egg yolk if you want to experiment. The additional egg yolk adds more fat, creating a fudgier brownie.

3 brownies in a stack with scoop of vanilla ice cream on top

Glass or metal pan to bake brownies

I used a glass 8×8 inch baking pan because that’s what I have in my kitchen!

You can use a metal pan and I would recommend decreasing the baking time by 5 minutes. Metal pans heat up faster and can produce chewier brownies.

How to tell if brownies are done

To determine if brownies are done, perform a toothpick test by inserting a toothpick into the center. If it comes out with a few moist crumbs, the brownies are done. Additionally, look for set edges and a shiny, crackled crust on the top of the brownies.

Box Brownie Recipe Variations

You can customize these brownies exactly how you like them!

Add nuts. Mix in chopped walnuts, chopped pecans or sliced almonds for a crunchy texture and nutty flavor.

Add chocolate or chopped candy bars. Think chocolate chips, white chocolate chips, butterscotch chips, peanut butter chips, chopped peanut butter cups.

Bring on the mint. Add chopped andes mints, crushed candy canes, peppermint patties or mint extract for an extra minty flavor. I think mint and chocolate is the best!

Swirl. Swirl in nutella, peanut butter, or cream cheese for an added surprise.

Frost them. Bring the chocolate flavor up a notch by frosting the brownies. See all of our frosting options. Coffee frosting on brownies is right up my alley!

Brownies a la Mode. Add caramel syrup, crushed potato chips, or chopped chocolate chip cookies for extra decadent brownies!

brownies in glass pan on white background

Pro Tips on How To Make Box Brownies Better

Cut brownies cleanly

To get really nice clean brownie squares, I like to refrigerate my brownies for at least 30 minutes before cutting.

Then I use a long 8 inch chef’s knife to cut them. But here’s the most important tip, wipe the knife CLEAN between each cut. Yes, it’s annoying, but it works!

Freeze brownies

Make the brownies and allow them to cool completely.

Cut them into squares, wrap 4 at a time in aluminum foil (wrap well), then cover them in plastic wrap and store in a freeze ziplock bag for up to 3 months.

To thaw: place in the fridge over night.

brownies cut into squares stacked on top of each other

Can I bake these in a 9×13 inch pan?

You can bake the brownies in a 9×13 inch pan for 25-32 minutes. If you allow the recipe as stated and bake in a 9×13 inch pan, the brownies will not be as thick because the pan is larger.

You could double the recipe and bake in a 9×13 inch pan for thicker brownies. The baking time would be 40-60 minutes.

What to serve with this Boxed Brownie Recipe

  • Ice Cream: Serve warm brownies with a scoop of vanilla ice cream for a classic combination. The warm and fudgy brownie pairs perfectly with the cool and creamy ice cream. You can even add brownie pieces to a homemade hot fudge sundae.
  • Whipped Cream: Top your brownies with a dollop of whipped cream for a light and fluffy contrast. Love chocolate? Serve with chocolate whipped cream.
  • Berries: Fresh berries such as strawberries, raspberries, or blueberries add a fresh and fruity element to the rich brownies.
  • Caramel Sauce: Drizzle warm caramel sauce over the brownies for a sweet and gooey addition.

How to store this Boxed Brownie Recipe

To store brownies, allow them to cool completely, then cut them into individual portions. Place the brownies in an airtight container or wrap them tightly in plastic wrap, and store them at room temperature for a few days or in the refrigerator for longer shelf life.

Recipe Reviews

These turned out so good and moist and indulgent!  I didn’t have espresso powder but had about two tablespoons of strong coffee left so I added it with the milk to equal the liquid amount and it turned out great!  My husband and 2 year old wolfed down their trial piece and promptly asked for more!  

-Ami

Normally I don’t comment on these kinds of recipes, but it was so good. Without a doubt the best brownies I’ve ever had- including the countless ones I’ve made from scratch and even the deluxe brownie at my favorite restaurant- these simple modifications to a box of brownie mix make it the best brownies ever. Period. 

-Grace

More Recipes


4.39 from 533 ratings

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A Better Brownies Box Recipe

By: Beth
Prep Time: 15 minutes
Cook Time: 37 minutes
Total Time: 52 minutes
Servings: 12 servings
I’m letting you in on my family’s favorite easy brownie recipe, with all my best brownie mix hacks to make box brownies so much better! Just a few additional “secret ingredients” and no one will ever know your brownies came from a box!

Ingredients

  • 2 large eggs
  • 1 stick unsalted butter, melted, 1/2 cup
  • cup buttermilk or milk
  • 18.3 oz brownie mix, 18.4 oz is fine too!
  • ¼ cup cocoa powder
  • 1 tsp espresso powder, optional, but makes chocolate flavor richer, the brownies will NOT taste like coffee. Can use 1/4 cup brewed coffee or 1 & 1/2 tsps instant coffee in place of espresso powder.

Instructions 

  • Preheat the oven to 350ºF. 
  • Line a 8×8 inch square pan with parchment paper and spray with non-stick cooking spray. Set aside.
  • In a mixing bowl, combine the eggs, melted butter, buttermilk, brownie mix, cocoa powder and espresso powder and beat with an electric mixer on low until combined, about 1 minute. 
  • Pour the brownie batter into the prepared pan. Spread evenly with a spatula.
  • Bake for 37-40 minutes or until a toothpick inserted in the center comes out clean.
  • Allow the brownies to cool. Remove the brownies from the pan using the parchment paper. Slice and serve. 
  • *Note: bake in a 9×13 inch pan for 25-32 minutes. The brownies will not be as thick. 

Video

Notes

Should I use a glass or metal pan to bake brownies?

I used a glass 8×8 inch baking pan because that’s what I have in my kitchen! You can use a metal pan and I would recommend decreasing the baking time by 5 minutes. Metal pans heat up faster and can produce chewier brownies.

Can I add nuts or other add-ins to these brownies?

Definitely! Add 3/4 cup to 1 cup of add-ins. You could add any variety of chopped nuts, chocolate chips, peanut butter chips, mint pieces, caramel bits, reese’s pieces, etc.

Nutrition

Calories: 279kcal | Carbohydrates: 35g | Protein: 4g | Fat: 14g | Saturated Fat: 6g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 5g | Trans Fat: 1g | Cholesterol: 52mg | Sodium: 147mg | Potassium: 53mg | Fiber: 1g | Sugar: 22g | Vitamin A: 291IU | Calcium: 17mg | Iron: 2mg
Like this recipe? Rate and comment below!

About Beth

I believe that everyone should have a go-to dessert to bring to parties! With hundreds of recipes, I'll help you find yours!

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4.39 from 533 votes (528 ratings without comment)

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142 Comments

  1. This is by far the best way to give a helping hand to box brownies. My family and friends loved them. Thank you!!! ❤️

    1. I would recommend using a 18.3 or 18.4 oz box – you could try it with the 20 oz box, but I’m not sure how it will turn out.

    1. Without personally testing it myself, I’m not sure if doubling it would be enough or what the bake time would be! Report back if you try it!

  2. 3 stars
    Not great. Took out of oven 10 min before time was up and still pretty dry. Had a good flavor though.